Mercedes finally showed the capability of their new W06 when it comes to speed as well as reliability as Nico Rosberg blew away the rest of the field on the second day of the final pre-season test in Barcelona.
Using the faster soft tyres for the first time this season, Rosberg produced the fastest time through six days of testing at the Circuit de Catalunya in 1min 22.792sec.
The German`s time was more than seven tenths of a second quicker than the previous best time set by Williams` Felipe Massa on Thursday.
Williams remained the closest challengers for the reigning double world champions as Valtteri Bottas was second fastest, albeit over a second back on Rosberg, whilst Brazilian rookie Felipe Nasr completed another good day for Sauber as he went third quickest in a marathon 140-lap day.
There was even some encouragement for the under fire McLaren-Honda partnership as Jenson Button managed 101 laps before bringing his session to an early end when he broke down with just 15 minutes of the day left to run.
Meanwhile, Force India finally unveiled their VJM08 car for the upcoming season and also had a positive day as Nico Hulkenberg managed 76 laps.
Results from the morning session on day two of the third pre-season test in Barcelona:
1. Nico Rosberg (GER/Mercedes) 1:22.792 (106 laps)
2. Valtteri Bottas (FIN/Williams) 1:23.995 (90 laps)
3. Felipe Nasr (BRA/Sauber) 1:24.071 (140 laps)
4. Sebastian Vettel (GER/Ferrari) 1:25.339 (142 laps)
5. Jenson Button (GBR/McLaren) 1:25.590 (101 laps)
6. Pastor Maldonado (VEN/Lotus) 1:26.705 (139 laps)
7. Max Verstappen (NED/Toro Rosso) 1:26.766 (139 laps)
8. Daniil Kyvat (RUS/Red Bull) 1:26.965 (83 laps)
9. Nico Hulkenberg (GER/Force India) 1:28.412 (76 laps)